aboutsummaryrefslogtreecommitdiffstats
path: root/lv2/event/event.meta.ttl
blob: 22d8f920226de89844b7659131fbbdfdb471592f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
@prefix dcs: <http://ontologi.es/doap-changeset#> .
@prefix doap: <http://usefulinc.com/ns/doap#> .
@prefix ev: <http://lv2plug.in/ns/ext/event#> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix lv2: <http://lv2plug.in/ns/lv2core#> .
@prefix rdfs: <http://www.w3.org/2000/01/rdf-schema#> .

<http://lv2plug.in/ns/ext/event>
	a doap:Project ;
	doap:license <http://opensource.org/licenses/isc> ;
	doap:name "LV2 Event" ;
	doap:shortdesc "A port-based real-time generic event interface." ;
	doap:created "2008-00-00" ;
	doap:developer <http://drobilla.net/drobilla#me> ,
		<http://lv2plug.in/ns/meta#larsl> ;
	doap:release [
		doap:revision "1.12" ;
		doap:created "2014-08-08" ;
		doap:file-release <http://lv2plug.in/spec/lv2-1.10.0.tar.bz2> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Minor documentation improvements."
			]
		]
	] , [
		doap:revision "1.10" ;
		doap:created "2013-01-13" ;
		doap:file-release <http://lv2plug.in/spec/lv2-1.4.0.tar.bz2> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Fix incorrect return type in lv2_event_get()."
			]
		]
	] , [
		doap:revision "1.8" ;
		doap:created "2012-10-14" ;
		doap:file-release <http://lv2plug.in/spec/lv2-1.2.0.tar.bz2> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Make event iterator gracefully handle optional ports."
			] , [
				rdfs:label "Remove asserts from event-helper.h."
			] , [
				rdfs:label "Use more precise domain and range for EventPort properties."
			] , [
				rdfs:label "Use consistent label style."
			]
		]
	] , [
		doap:revision "1.6" ;
		doap:created "2012-04-17" ;
		doap:file-release <http://lv2plug.in/spec/lv2-1.0.0.tar.bz2> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Fix bug in lv2_event_reserve()."
			] , [
				rdfs:label "Fix incorrect ranges of some properties."
			] , [
				rdfs:label "Merge with unified LV2 package."
			]
		]
	] , [
		doap:revision "1.4" ;
		doap:created "2011-11-21" ;
		doap:file-release <http://lv2plug.in/spec/lv2-event-1.4.tar.bz2> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Update packaging."
			]
		]
	] , [
		doap:revision "1.2" ;
		doap:created "2011-05-26" ;
		doap:file-release <http://lv2plug.in/spec/lv2-event-1.2.tar.bz2> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Add build system (for installation)."
			] , [
				rdfs:label "Convert documentation to HTML and use lv2:documentation."
			] , [
				rdfs:label "Use lv2:Specification to be discovered as an extension."
			]
		]
	] , [
		doap:revision "1.0" ;
		doap:created "2010-11-24" ;
		doap:file-release <http://lv2plug.in/spec/lv2-event-1.0.tar.gz> ;
		dcs:blame <http://drobilla.net/drobilla#me> ;
		dcs:changeset [
			dcs:item [
				rdfs:label "Initial release."
			]
		]
	] ;
	lv2:documentation """

<span class="warning">This extension is deprecated.</span> New implementations
should use <a href="atom.html">LV2 Atom</a> instead.

This extension defines a generic time-stamped event port type, which can be
used to create plugins that read and write real-time events, such as MIDI,
OSC, or any other type of event payload.  The type(s) of event supported by
a port is defined in the data file for a plugin, for example:

    :::turtle
    &lt;http://example.org/some-plugin&gt;
        lv2:port [
            a ev:EventPort, lv2:InputPort ;
            lv2:index 0 ;
            ev:supportsEvent &lt;http://lv2plug.in/ns/ext/midi#MidiEvent&gt; ;
            lv2:symbol "midi_input" ;
            lv2:name "MIDI input" ;
        ] .

"""^^lv2:Markdown .

ev:EventPort
	lv2:documentation """

Ports of this type will be connected to a struct of type LV2_Event_Buffer,
defined in event.h.  These ports contain a sequence of generic events (possibly
several types mixed in a single stream), the specific types of which are
defined by some URI in another LV2 extension.

"""^^lv2:Markdown .

ev:Event
	a rdfs:Class ;
	rdfs:label "Event" ;
	lv2:documentation """

An ev:EventPort contains an LV2_Event_Buffer which contains a sequence of these
events.  The binary format of LV2 events is defined by the LV2_Event struct in
event.h.

Specific event types (e.g. MIDI, OSC) are defined by extensions, and should be
rdfs:subClassOf this class.

"""^^lv2:Markdown .

ev:TimeStamp
	lv2:documentation """

This defines the meaning of the 'frames' and 'subframes' fields of an LV2_Event
(both unsigned 32-bit integers).

"""^^lv2:Markdown .

ev:FrameStamp
	lv2:documentation """

The default time stamp unit for an LV2 event: the frames field represents audio
frames (in the sample rate passed to intantiate), and the subframes field is
1/UINT32_MAX of a frame.

"""^^lv2:Markdown .

ev:generic
	lv2:documentation """

Indicates that this port does something meaningful for any event type
(e.g. event mixers, delays, serialisers, etc).

If this property is set, hosts should consider the port suitable for any type
of event.  Otherwise, hosts should consider the port 'appropriate' only for the
specific event types listed with :supportsEvent.  Note that plugins must
gracefully handle unknown event types whether or not this property is present.

"""^^lv2:Markdown .

ev:supportsEvent
	lv2:documentation """

Indicates that this port supports or "understands" a certain event type.

For input ports, this means the plugin understands and does something useful
with events of this type.  For output ports, this means the plugin may generate
events of this type.  If the plugin never actually generates events of this
type, but might pass them through from an input, this property should not be
set (use ev:inheritsEvent for that).

Plugins with event input ports must always gracefully handle any type of event,
even if it does not 'support' it.  This property should always be set for event
types the plugin understands/generates so hosts can discover plugins
appropriate for a given scenario (e.g. plugins with a MIDI input). Hosts are
not expected to consider event ports suitable for some type of event if the
relevant :supportsEvent property is not set, unless the ev:generic property for
that port is also set.


"""^^lv2:Markdown .

ev:inheritsEvent
	lv2:documentation """

Indicates that this output port might pass through events that arrived at some
other input port (or generate an event of the same type as events arriving at
that input).  The host must always check the stamp type of all outputs when
connecting an input, but this property should be set whenever it applies.


"""^^lv2:Markdown .

ev:supportsTimeStamp
	lv2:documentation """

Indicates that this port supports or "understands" a certain time stamp type.
Meaningful only for input ports, the host must never connect a port to an event
buffer with a time stamp type that isn't supported by the port.

"""^^lv2:Markdown .

ev:generatesTimeStamp
	lv2:documentation """

Indicates that this port may output a certain time stamp type, regardless of
the time stamp type of any input ports.

If the port outputs stamps based on what type inputs are connected to, this
property should not be set (use the ev:inheritsTimeStamp property for that).
Hosts MUST check the time_stamp value of any output port buffers after a call
to connect_port on ANY event input port on the plugin.

If the plugin changes the stamp_type field of an output event buffer during a
call to run(), the plugin must call the stamp_type_changed function provided by
the host in the LV2_Event_Feature struct, if it is non-NULL.

"""^^lv2:Markdown .

ev:inheritsTimeStamp
	lv2:documentation """

Indicates that this port follows the time stamp type of an input port.

This property is not necessary, but it should be set for outputs that base
their output type on an input port so the host can make more sense of the
plugin and provide a more sensible interface.

"""^^lv2:Markdown .